Contralaterally Controlled FES for Hand Opening in Hemiplegic Cerebral Palsy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Contralaterally Controlled FES for Hand Opening in Hemiplegic Cerebral Palsy (NCT02925455), a randomized na study. The primary outcome is Change in Assisting Hands Assessment Logit Score at End of Treatment.

2. Clinical Question

3. Trial Design

This was a pilot randomized controlled trial with a parallel-group structure. The registry lists the allocation as randomized and the masking as single. It does not report who was masked, what procedures were used to maintain masking, or whether masking was assessed. The trial status is completed. The recorded start date is 2016-10-16, and the primary completion date is 2019-12-31.

The two groups received hand-therapy video games and task practice. The experimental group also received CCFES to assist hand opening during practice; the comparison group did not receive the stimulation device. The brief description outlines clinic sessions guided by a therapist and home sessions completed independently or with caregiver assistance. It describes a treatment period of 6 weeks and assessments at baseline, mid-treatment, end of treatment, and 3 mo follow-up. The primary outcome entry specifies the comparison between prior to treatment and the end of 6 weeks of treatment.

The registry’s enrollment field lists 15. The brief description says that twenty participants will be randomized, phrased as a plan. The posted primary outcome gives results for the Stimulation + Video Games arm with n=9 and the Video Games (no Stimulation) arm with n=6. These record entries should be read in their stated contexts; the brief description alone does not establish how many participants were ultimately randomized or assessed at every time point.

The record identifies the study as a pilot and lists MetroHealth Medical Center as sponsor. The phase is listed as NA. The registry record does not report the randomization method, allocation concealment procedures, a formal sample-size justification, or the detailed statistical analysis plan.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Change in Assisting Hands Assessment Logit Score at End of Treatment, measured over 2 time points: prior to treatment and at end of 6 weeks of treatment.

The primary endpoint is change in the Assisting Hands Assessment Logit Score at the end of treatment. Participants performed bimanual tasks in a game while being video recorded. The affected arm’s involvement was scored from the video and converted to a logit score on a 0-100 scale. A higher score indicates a better outcome according to the endpoint description.

The measure focuses on how the affected arm participates in activities requiring both hands. That makes it relevant to the study’s intended question about upper-extremity motor function in children with hemiparesis, rather than measuring only whether the hand can open under a single isolated condition. Video scoring also provides a way to assess performance during a task, although the registry record does not describe the scoring procedures in enough detail to evaluate assessor training, reliability, or masking.

The posted endpoint is a change from before treatment to the end of the 6-week treatment period. The reported mean change is 2.63 for Stimulation + Video Games, with a 95% confidence interval from 0.415 to 4.85. For Video Games (no Stimulation), the reported mean change is 4.33, with a 95% confidence interval from 2.44 to 6.23. The record gives these summaries separately by group. It does not report a direct estimate of the difference in mean change between groups, which is the quantity needed to describe the randomized treatment contrast and its uncertainty.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The endpoint is continuous: it is a score on a scale, and the registry identifies the summary parameter as a mean. A mean describes the central level of a group’s observations, or, for this endpoint, the average reported change. It can be useful for comparing groups, but the mean alone does not convey how spread out participant-level changes were. The record reports confidence intervals rather than standard deviations for the arm-level changes.

What does a 95% confidence interval describe?

In general, a confidence interval expresses uncertainty in an estimate under the statistical method used to calculate it. It is not a range intended to contain 95% of individual participant values, and it is not a guarantee that the true value lies inside the particular interval. Here, each interval is attached to a mean change for one group: 0.415 to 4.85 for Stimulation + Video Games and 2.44 to 6.23 for Video Games (no Stimulation). These intervals communicate precision for those separate means. They do not directly give uncertainty for the difference between the means.

For a randomized trial, the between-group effect is generally the relevant comparison because both groups can change during treatment. A direct contrast estimates how the groups’ outcomes differ, according to the chosen analysis. Its confidence interval would show the precision of that contrast. The registry record does not post this contrast or its interval. No new contrast should be inferred by subtracting the displayed means, since such a calculation would not supply the missing analysis details or the uncertainty of the difference.

Why are arm-level intervals not a test of the treatment contrast?

In general, the uncertainty of a difference depends on the uncertainty in both group estimates and on the analysis used to combine them. Looking at two separate intervals is not equivalent to calculating an interval or test for the difference. Even when the arm means and intervals are available, they do not identify all choices that may have been made in the sponsor’s analysis. The registry record lists no posted analysis for the primary comparison, and its analysis count is 0. It also does not report a p-value for the between-group result. A significance claim about the randomized contrast is therefore not supported by the posted endpoint summaries.

What do planning illustrations mean?

The registry record describes sample-size illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between the groups, and a normal approximation. The illustrated effect is a stated fraction of the observed effect. Such calculations are planning exercises: they show how a chosen effect assumption relates to a hypothetical design under stated assumptions. They are not observed power for this trial and do not demonstrate that the study had a particular probability of detecting an effect. The record does not give a sample-size justification from the trial’s own design, and no unreported planning values should be inferred.

In general, planning calculations based on an observed effect can be especially uncertain when the estimate comes from a pilot study. The observed effect may not represent the effect that would be expected in a later study, and a planning exercise does not resolve the uncertainty in the trial’s direct treatment contrast. The registry record’s stated assumptions should be read as assumptions for illustration, not as evidence that a particular sample size was prespecified or achieved.

What can be said about dispersion?

In general, over-dispersion means that the observed variation is larger than a statistical model expects. It matters because a model that understates variation can produce confidence intervals that are too narrow and tests that are too optimistic. The registry record does not report a dispersion estimate or an over-dispersion assessment for this continuous endpoint. The arm-level confidence intervals convey uncertainty around each mean, but they do not reveal the full distribution of individual changes or permit a separate evaluation of model fit.

More broadly, the registry record does not report the detailed model, covariates, assumptions, or missing-data method used for the primary endpoint. It is not possible to determine from the posted summaries whether the analysis used a model adjusted for baseline, a complete-case approach, or another method. These details matter because they define precisely what was estimated and how uncertainty was calculated. The reported group means and intervals remain useful descriptive summaries, but they cannot replace a transparent account of the randomized comparison and its analysis.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists five outcome measures and one posted secondary outcome: Change in Melbourne 2 Motor Assessment at End of Treatment. The primary endpoint is the Assisting Hands Assessment Logit Score change at the end of treatment. The record does not describe a multiplicity adjustment, a hierarchy for testing outcomes, or a procedure for controlling the chance of false-positive findings across multiple analyses. It also does not report the statistical analysis plan needed to determine which outcomes or comparisons were prespecified for confirmatory testing.

Because the posted record includes more than one outcome measure, readers should distinguish the primary endpoint from secondary outcomes and avoid treating every available result as an independent confirmation. The registry record does not provide enough detail to determine how multiplicity was handled or whether all planned outcomes are reported. The analysis count is 0, and no further primary-comparison analysis is posted in the record.

The endpoint timeframe compares assessment before treatment with assessment at the end of 6 weeks of treatment. Although the brief description mentions baseline, mid-treatment, end-of-treatment, and 3 mo follow-up assessments, the primary endpoint entry specifies the end-of-treatment comparison. The record does not report the number of missing observations at each time point, reasons for missingness, or how missing endpoint values were handled. It also does not define an intention-to-treat or per-protocol analysis population, or state how participants who did not complete treatment were handled.

These omissions limit interpretation of the arm-level estimates and make it difficult to assess whether the posted results represent all randomized participants or a subset with endpoint data. The registry record does not report sensitivity analyses for missing data. Without those details, the degree to which missing observations could affect the results cannot be evaluated from the posted record.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry record reports no serious adverse events in either posted group. For Stimulation + Video Games, 9 participants were listed as at risk and 0 as affected by a serious adverse event. For Video Games (no Stimulation), 6 were listed as at risk and 0 as affected. The record also lists 0 deaths in each group. These are the reported safety counts for the groups and outcomes recorded in the registry.

A count of zero means that no serious adverse events were recorded among the participants included in the registry’s safety entry; it does not establish that no adverse events of any kind occurred. The record separately lists 0 other adverse events for the Stimulation + Video Games group and 0 for the Video Games (no Stimulation) group. It does not give event terms for serious adverse events, and the serious-event term list is empty.

Safety counts are descriptive. They do not establish that the interventions caused or prevented an event, and they cannot rule out uncommon harms. Interpretation also depends on how events were defined, collected, monitored, and attributed. The registry record does not report those procedures, the duration of safety monitoring, or whether all randomized participants contributed to the safety assessment. The counts should therefore be read as the safety information posted in the registry, not as a comprehensive account of all possible events.

12. What the Result Does, and Does Not, Mean

The posted outcome indicates that both groups had a positive mean change in Assisting Hands Assessment Logit Score over the specified treatment period. The mean change was 2.63 for Stimulation + Video Games and 4.33 for Video Games (no Stimulation). The 95% confidence intervals describe uncertainty around each group’s mean change. The endpoint description says higher scores indicate a better outcome.

These results do not establish whether adding CCFES led to a larger or smaller change than the video-game and task-practice program alone. That question concerns the between-group contrast, which is not reported in the registry record. The mean change in one group cannot be interpreted as the effect of the assigned intervention by itself, and the two arm-specific intervals are not a substitute for a confidence interval for the contrast. The posted summaries also do not report a formal test of within-group change.

The record identifies this as a pilot randomized trial and gives group-specific participant counts of n=9 and n=6 for the primary outcome. The intervals indicate that the mean estimates have uncertainty, but the record does not post a direct estimate of the treatment contrast or the analysis details needed to assess its precision. It also does not report a threshold for a clinically meaningful score change. As a result, the clinical importance of the observed arm-level changes cannot be determined from these entries alone.

Nor do these results establish what would happen in other settings or populations. The registry describes children ages 6 to 17 with cerebral palsy and upper-limb hemiparesis, and the intervention includes both clinic-based and home practice. The record does not provide enough information to assess how closely the participants or delivery conditions represent other circumstances. A pilot result can describe the posted observations and inform questions for further study, but it should not be treated as definitive evidence for a treatment effect.

13. Why This Trial Matters Statistically

This trial is statistically informative as an example of the distinction between within-group change and a randomized comparison. The primary result is reported as a mean change separately for each group. Those summaries help describe what was observed over time, but the principal randomized question is whether the groups differed in their changes. A direct estimate and its uncertainty are needed to answer that question quantitatively. Their absence in the registry record is an important interpretive limitation, not a reason to substitute informal comparisons of the arm-level intervals.

The record also illustrates why confidence intervals matter alongside point estimates. Each mean change is accompanied by a 95% confidence interval, making uncertainty around the arm-specific estimates visible. Yet confidence intervals must be matched to the estimand of interest: uncertainty around separate group means is not the same as uncertainty around their difference. This distinction is important when readers encounter outcomes presented by arm without a corresponding comparison estimate.

The pilot designation makes transparent reporting especially useful. The record describes a small randomized study and includes planning illustrations based on an observed effect, but it does not report the trial’s own sample-size justification. Planning calculations based on observed results are not observed power and do not establish the precision of the randomized contrast. A clear account of the planned estimand, analysis, missing-data handling, and uncertainty would help readers distinguish exploratory description from a confirmatory treatment comparison.

Finally, the record shows the value of separating registry entries that have different meanings. The enrollment field lists 15, while the brief description states that twenty participants will be randomized; the primary-outcome arm entries give n=9 and n=6. Reporting these in context avoids treating a planned enrollment statement as a completed analysis count. Such distinctions are central to sound statistical interpretation of clinical trial records.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The registry record does not include a direct between-group estimate for the primary endpoint, a confidence interval for that estimate, or a comparison test. This prevents quantitative assessment of the randomized contrast from the posted outcome results. The arm-specific means and intervals are informative descriptions, but they do not determine the size or precision of the treatment-versus-comparator difference.

The record gives no standard deviations or participant-level outcome distributions for the primary endpoint. It therefore does not show the variability of individual changes, the presence of outliers, or how changes were distributed within either group. It also does not describe the scoring reliability or procedures used to score the recorded bimanual tasks. Masking is listed as single, but the identity of the masked party and the practical masking procedures are not reported in the registry record.

The enrollment field lists 15, the brief description says twenty participants will be randomized, and the primary endpoint entries report group counts of n=9 and n=6. The record does not explain the relationship among these figures or report participant flow, withdrawals, or the number assessed at each time point. It does not specify the primary analysis population, missing-data method, or whether the reported means include every randomized participant with available data.

The record also lacks a detailed statistical analysis plan, a sample-size justification, a defined threshold for meaningful change, and information about multiplicity handling. Although the brief description mentions several assessment times, the primary outcome is specified at the end of treatment; results for other time points are not part of the posted primary endpoint entries. These limitations make the posted results most useful as a descriptive account of the registered endpoint, rather than a complete statistical report of the randomized comparison.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Contralaterally Controlled FES for Hand Opening in Hemiplegic Cerebral Palsy — NCT02925455.
• Registry record last updated 2021-06-22; status last verified 2021-06.
• Results first posted 2021-06-22.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

NCT02925455 is a completed pilot randomized controlled trial of contralaterally controlled functional electrical stimulation for hand opening in hemiplegic cerebral palsy. The registry lists a parallel design, single masking, MetroHealth Medical Center as sponsor, a start date of 2016-10-16, and primary completion on 2019-12-31. The study description concerns children ages 6 to 17 with cerebral palsy and upper-limb hemiparesis.

The primary outcome is change in Assisting Hands Assessment Logit Score from before treatment to the end of 6 weeks of treatment. The reported mean change is 2.63, with a 95% confidence interval of 0.415 to 4.85, for Stimulation + Video Games. For Video Games (no Stimulation), the mean change is 4.33, with a 95% confidence interval of 2.44 to 6.23. The registry record does not post a direct between-group estimate or its uncertainty.

The record lists enrollment as 15, while its brief description states that twenty participants will be randomized. The primary outcome entries give n=9 and n=6 for the two groups. No serious adverse events or deaths are listed in either group. Details of missing-data handling, analysis populations, multiplicity, and the primary comparison analysis are not reported in the registry record.